Cutter chain construction



c. B; KREKELER ETAL 2,851,261

CUTTER CHAIN CONSTRUCTION Sept. 9, 1958 Filed July 10, 1956 Ike-.4.

15 INN aft/1577. E,

TO RN EYS.

2,351,261 CUTTER CHAIN CONSTRUCTION.

Claude B. Krekeler, John R. Cartlidge, and Armin 0.

Bruestle, Cincinnati, Ohio, assignors to The Cincinnati Mine Machinery Company, Cincinnati, Ohio, a corporation of Ohio Application July 10, 1956, Serial No. 597,002

9 Claims. (Cl. 262-33) The invention relates to mining machinery commonly used in the mining of coal in which a cutter chain, alternate links carrying-cutter bits, is driven about the periphery of a cutter bar within a groove or channel at the edges of the cutter bar. A serious problem is encountered in'the use of such machinery in that, during the cutting operation, fine cuttings or dust tend to accumulate and pack in the cutter bar channel beneath the chain. The packing difficulty is enhanced by conditions of moisture in the cuttings, the presence of clay veins in the coal, and the like. Because of the packing, the chain is tightened and frictional resistances are increased. The building up of dust sometimes will make the chain so taut as to stop a fifty or seventy-five horse- I power motor.

A primary object of the invention is the provision of means and a method for alleviating the aforesaid packing.

More specifically, it is an object of the invention to provide means-and a method for breaking up or disintegrating packed materials and for conveying them along the channel to a point at which they can be discharged therefrom.

Another object is the provision of means acting to stabilize the chain on the sprocket.

These and other objects of the invention which will be set forth hereinafter or will be apparent to one skilled in the art upon reading these specifications, are accomplished by that construction and arrangement of parts of which certain exemplary" embodiments will be de-.

scribed. Reference is made to the accompanying drawings, wherein:

Figure 1 is a top plan view of a cutter bar and chain.

Figure 2 is a partial side elevation of a pair of cutter chain links showing one application of the invention.

Figure 3 is a corresponding bottom plan view.

Figure 4 is a partial sectional view taken along the section line 4-4 of Figure 2.

Figure 5 is a partial sectional view taken along the section line 5-5 of Figure 2.

Figure 6 is a partial side elevation of a pair of cutter chain links showing another application of the invention.

Figure 7 is a corresponding bottom plan view.

Cutter chains are made up of single link elements 1 and double link elements 2. The double link elements are characterized by a pair of spaced checks 3 and 3a between which the ends of the singlelink elements are received. The spaced checks are formed integrally with a block 6 which is perforated so as to constitute a socket for the reception of the shanks of cutter bits 7, or the shanks of bit holders for renewable cutter bits. The link elements are held together by pintles. Such organizations of elements are well known in this art, and while they may take various specific forms, further description is not required herein because the specific forms are not limitations on the present invention.

In a mining machine (Figure 1), the body of which is partially indicated at 8, there is a driven sprocket 9 over which one end of the cutter chain is engaged. The

nitecl States Patent 0 remainder of the chain passes around a cutter bar 10 of elongated shape. The cutter bar has side plates, one of which is shown at 11. These together with interior rails 12, form a channel in which the body of the chain rides, the bits 7 extending outwardly in cutting position. It is usual practice to provide for some adjustment in the length of the cutter bar to permit taking up slack in the chain. The double-link chain elements may have laterally extending portions 13 approaching the side plates 11. All of this is conventional, and may be varied.

The packing of fine cuttings occurs primarily in the groove or channel formed by the side plates 11 and rails 12 of the cutter bar; and the chain begins to ride over a bed of the packed material becoming progressively more and more tensioned, the frictional resistance also greatly increasing.

As a first step toward relieving this difliculty, the central inside bottom edge portions of the cheeks 3 and 3a of the double-link chain elements 2 are hollowed out as generally indicated at14 and 15 in Figures 3 and 5 while the central bottom edge portion of the single link element 1 are hollowed from both sides as indicated at 16 and 17 in Figure 4. The hollows may have various shapes but it is convenient and believed to be advantageous to make them arcuate in conformation as shown. They may be formed in various ways. Thus the hollows may be produced by suitable configurations of the dies in the forging operation by which the single and double-link elements are manufactured. Again, the hollows may be cut in the completed link elements by means of broaches or milling cutters.

The hollows which have been described and illustrated perform certain useful functions. The cutter chain link elements, the shapes of the lower edges of which have been modified by the hollows, exhibit a diminished tendency to ride over and pack or consolidate the fine cuttings in the bottom of the grooves. Instead they tend to disrupt or break up masses of fine cuttings to inhibit the packing thereof. They exhibit a tendency to cut down through layers of packed fines; and they also have an enhanced tendency to convey the fines, or cause them to travel with the chain to a point at which they can be disposed of. Such a point may be the inner end of the cutter bar or any orifice or interruption in the portions of the side plates 11 forming part of the channel in which the cutter chain rides.

However, merely forming the hollows in the cheeks of the link elements as shown and described has not proved a complete solution to the problem. It has been found that the various useful functions described above can be enhanced by providing in the hollows substantial roughnesses, pgojections, beads, ribs, or the like. These have a marked tendency not only to increase the breaking up of aggregates of fines which otherwise would pack at the bottom of the channel, but also speed up and facilitate a conveying of the fines.

The roughening configurations in the hollows can be produced at the time the hollows are formed as for example in forging or cutting. They can also be produced on the walls of relatively smooth hollows. In Figures 2 to 5, the numeral 18 indicates roughened or beaded ribbed configurations formed by depositing weld metal on the inner surfaces of the hollows as by electric welding or torch welding techniques. The weld metal itself is derived from a weld rod or other source.

A still more effective construction is that shown in Figures 6 and 7. Here, the inner, bottom edges of the cheeks 3 and 3a of the double link element are again hollowed out as at 19 and 20; but ribs 21 and 22 are left intermediate the hollowed portions. Similarly the single link element 1 is hollowed laterally on its bottom edges as at 23 and 24; but a central rib or ribs 25 is left as illustrated. Wherethe'wh'ole bottom edge of the single link element 1 is 'cut back'cent rally slightly as illustrated at 26 in Figure 6, it has been found advantageous-to permit therib 25, toextend-downwardly to,.the..

lower edge plane of the chain;

The lugsof'ribs which'ha ve been described are especially effective in breaking up and conveying fine cuttings which otherwisewould tendtopackin the cutter barcha'iinel. Thisisresp'ecially 'tr'ue'ofth'e projecting rib on the single link element. The ,ribs on' the double link element also. have a function in'fhelping to stabilize the chainby presentingalarger, bearing area to the sprocket toothat' the 'sides,fthus"rejsis'ting side-wise pressure.

In producing the stmcture's of'Figui'es 6 and 7, the hollows may be formedbysuitab le cutters, in such a way as to leave the ribs in place" Orthe hollows and ribs may be formed by suitably fsh'ap'ed 'dies during the initial forging of the structures; Morethan one rib per hollow can be employed if desired, but this has not beenfound necessary.

Modifications may be" made .in'theinvention without departing from the spirit'of it.-' The invention having thus been described in certain exemplary'embodiments, what is claimed as new and desired to 'be secured by Letters Patent'is:

1. A cutter chain for a mining machine-comprising link elements having singlecheeks. and link elements having double, spaced cheeksbetween which the ends of the single cheek elements are received and to which they are fastened by meansof'pintles, the bottom portion of the side edges of s'aidsingle cheek elements having inwardly extending tapering hollows, and the inner bottom portions of the side edges ,of the double cheek elements having outwardly extending tapering hollows, the inner surfacesof' the said hollows being provided with projections of substantialdepth.

2. The structure claimed in'iclairn 1 wherein the said projections are beaded ribbed configurations formed by depositing weld metal on the inner surfaces of the said hollowed portions.

3. The structure claimed in claim 1 wherein the said projections are ribs formed-substantially centrally of the said hollowed portions;

4. The structure claimed in claim 1 wherein the said projections are ribs formed substantially centrally of the said hollowed portions, the under surface of said single cheek element being cut back slightly adjacent the said ribs.

5. In a cutter chain for a mining machine, a link element having a single cheek, the bottom central portion of the side edges of said element having inwardly extending hollows tapering out to the side edges of said element, the inner surfaces of said hollows being provided with at least one projection of substantial depth.

6. In a cutter chain for a mining machine, a link element having double, spaced cheeks, the inner bottom central portions of the side edges of said double cheeks having outwardly extending hollows tapering outwardly to meet the said side edges, the inner surfaces of said hollows being provided with projections of substantial depth.

7. In a cutter chain for a mining machine, a link element, the bottom central portion of at least one side edge of said element. having an inwardly extending hollow tapering out to the said side edge, whereby the bearing of said element at its bottom on a guide over which said element'rides is diminshed in. area, and whereby any cuttings entering said hollow are moved laterally of said element.

8. The structure claimed in claim 7, wherein said element has substantially similar hollows extending inwardly from both of its side edges at the bottom central portion of the said element.

9. A cutter-chain for a mining machine comprising link elements having single cheeks and link elements having double, spaced cheeks between which the ends of the single cheek elements are received and to which they are fastened by means of pintles, the bottom portion of the side edges of said single cheek elements having inwardly extending hollows tapering outwardly to the said side edges, and the inner bottom portions of the side edges of the double cheek elements having outwardly extending hollows tapering inwardly to the said side edges, whereby the bearing of said elements on guide means at their bottoms is diminished in area, and whereby cuttings entering the said hollows are moved laterally of the said elements.

References Cited in the file of this patent UNITED STATES PATENTS 

